crossley



Jan. 8, 1924. 1,480,534

A. CROSSLEY VARIOCOUPLER Filed Aug. 16 1922 2-Sheets-Sheet X Jan. 8, 1924. 1,480,534

A. CROSSLEY VARIOCOUPLER Filed Aug. 16. 1922 2 Sheets-Sheet!- 3 wwnloz a *2 r N W H 7 61mm,

Patented Jan. 8, 1924.

UNITED STATES PATENT OFFICE.

ALFRED CROSSLEY, OF \VASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO THE HAR'IMAN ELECTRICAL MANUFACTURING COMPANY, OF MANSFIELD, OHIO, A

CORPORATION.

VARIOCOUPLER.

Application filed August 16, 1922. Serial No. 582,254.

To all whom it may concern:

.Be it known that I, Anruno Cuossnnr, a citizen of the United States, residing at ashington, in the District of Columbia, have invented a certain new and useful Improve ment in a Variocoupler, of which the following is a specification. I

My invention relates broadly to signaling systems and more particularly to a variocouplcr for connection in radio frequency circuits in such systems.

One of the objects of my invention is to provide a variocoupler having large elect-mmagnetic coupling with minimum electrostatic coupling.

Another object of my invention is to pro vide a variocoupler construction by which a more perfect zero coupling may be obtained than in any construction of variocouplcr heretofore proposed. 7

Another object of the invention is to pro vide a variocoupler which may be connected in a cincuit and. arranged to secure extremely selective tuning of the circuits.

Other objects f the invention will appear from the specification hereinafter following by reference to the accompanying drawings in which Figure 1 is a side elevation of the variocoupler partially in half section; Fig. 2 is a front elevation of the variocoupler par tially broken away to show the rotor in section on lines 2- 2 of Fig. 1; Fig. 3 is a top plan view of the variocoupler; Fig. 4 is a perspective view of the variocoupler; Fig. 5 is a perspective view of one form of shaft employed as a mounting for oneside of the rotor of the variocoupler; Fig. 6 is a partial sectional View through line 66 of the rotor shaft of the varioconpler shown in Fig. 1; F ig. 7 is a view of one form of bearing support and terminal for one'end of the rotor of the variocoupler; Fig. 8 is a wiring'diagram showing the varioco-upler used in different positions in a regenerative election tube radio receiving circuit; and, Fig. 9 is a wiring diagram showing the variocoupler used in a radio -IeCe1Vil1g circuit employing electron tubes 7 arranged in a radio frequency-amplifying circuit for the reception of radio si als. 3

In my construction of variocoupler I ob tain a verylargeflelectromagnetic coupling of the circuits connected with the windings thereof by reducing to a minimum the effects radio frequency amplification the securing of zero coupling or very nearly ,zero coupling is of great importance. In present forms of variooouplers the passage of electrostatic energy from one circuit to another has the tendency of annulling the tuning effects and greatly reducing the selectivity of adjustment of the circuits. However, withthe negligible electrostatic capacity of my variocoupler, and when working near the zero coupling position, both circuits ma be tuned with great accuracy. This selectivity in tuning is particularly desirable for the reception ofsig'nals on difierent bands ofwavelengths within close proximity to each other. I r

In obtaining thesc results I provide a variocoupler including a rotor and a stator formin the primary and secondary windings which connect to the coupled circuits. Thestator of my variocoupler is tubular or cylindrical in form and its winding is arranged with minimum dielectric loss. The rotor of my variocoupler is formedin the shape of a disk mechanically mounted in a plane passing through the diameter'of the stator and at right angles to the axis thereof. The rotor comprises a hub with spokes radiall positioned therein. The winding carried bv the rotor is formed in the manner of a spider web-or fiat winding having its turns interweaved upon the 1 spokes and spirally built up to occupy the length of the spokes. The dielectric losses in both the primary and secondary windings are reduced to a minimum by reducing the area "of contact of the turns of each coil with the electric. The variocoupler may be connected in a variety of radio frequency ,circuits either in radio signaling systems orfin carrier wave line wire systems. 'When cmployed in the tuning circuit before a radio frequency electron tube amplifier the stator or primary winding is connected in the antenna ground system while the rotor is connected to the input circuit of the first stage of radio frequency electron tube amplifica tion. Maximum electromagnetic coupling occurs when the flat area of the rotor is in a position parallel -with the direction of the turns of the winding upon the stator while zero coupling occurs when the flat area of the rotor is approximately at right angles with the direction of the turns of the winding upon the stator. Intermediate degrees of coupling are obtained within the zero and maximum positions. In regenerative electron tube circuit arrangements the stator of thepyariocoupler may be connected in the grid circuit in series with the rotor of the variocoupler forming the' tuning circuit coupling. 'The rotor of the first mentioned variocou'pler is connected as a tickle! coil in the plate circuit and regeneration adjustedby changing the coupling between the rotor and stator.

"Referring to'the drawings, reference charactr I represents a base support with variocou'plerl The stator winding 2 of the vario coupler'isiwound'upon an insulated cylindrical' .'support4. The support 4 is secured to the bas e by members 5 one of which providesjneans' for"anchormg"the end of the stator winding'2secured to binding post 6f Thesilpport 4 lui'sa minimum of its area exposed g taeon'ta fi with the" turns of the stator Inj accomplishing this object I provide grooves? in-the insulating material. The l grooyesgreatly' reduce the dielectric losses 'zitfith'esame time that mechanical strength is retained. in the support in that the grooves are n t-cut entirely through the support. Within'tlie cylindrical stator suppoic't iT pivot a flat spider web wound rotor liaving; i t s winding indicated at S. The

rotor'isjormed upon a hub 10 with an uneven-number of round spokes 12 projecting therefrom. Through one of the spokes H. a rod 151is'passed being secured within the hub by nut 16 upon the threaded end of rod 15. The outer end of rod 15 carries flange 17 and bearing portion 18. The bearing does not contact with the walls of the cylindrical support 4 through. which it passes but is entirely supported in bearing strip 20 with leaf spring member 21 interposed between the inner surface of strip 20 and the flange 17. The strip 20 is screwed to the stator support 4 At the opposite side of the rotor I provide a bearing shaft 22 formed by reason of the uneven number ofspokes with a strip 2-1 embracing by means of screws 25 and 26 two of the spokes radiating from the hub. The bearing shaft 22 is provided with flange 27 adjacent the member 24 providing a face against which the leaf spring 28 exerts a constant pressure. The leaf spring 28 is secured in position by member 29 screwed to the outer walls of the stator support 4. The constant resilient force of leaf springs 21 and 28 provide means for rigidly adjusting the rotor in any position with reference to the stator winding. The inner end of the rotor winding 8 is secured to rod 15 and an electrical connection provided through the spoke 14', hearing 18, and resilient spring 2t to binding post 30. The winding upon the rotor frame is spirally formed and fashioned in a manner resembling a'spider web woven about the spokes radiating from the hub. The outer end of the rotor winding is connected to the member 24 and the electrical connection taken through shaft 22, leaf spring 28 and member 29 to binding post 31.

The variocoupler may be mounted immediately behind a panel and for permitting this assembly I provide screws 32 and34 the screw 32 passing into member 29 and the screw 34 passing through bushing 35 -and into the stator support 4.- -'lhe-shaft 22 projects through the'panel mounting and is provided with any desired form ofinsulatedknob by which adjustment of the position of the rotor with reference to the statormay be obtained as, for-example, in-dotted line positions 41 and 42. The stat01 winding anchored at binding post 6 may be-provided with intermediate connection points 36;=-37, 38 and 39, and tlie end 'of the winding'iinchored to bindingp'ost 40. FleXible connec ti'ons maybe taken from 'these seyeral points to contact points upon the panel and a switch provided to'se'lect'the desired number of electrical turns in'the statorgcircuih 1-; h

WVhileI have'fshown the roto'r'ascompris in'g a=hu 'b and a plurality ofspo'kessciewed into the periphery of the hub 'it-will be un deistood that the rotor frame maybe'moulded or formed 'from insulating materinl'iu'; one integral mass. r1;

The va riocouplerm be used in a variety of electrical circuits where 'extreme'nc'cumcy in tuning is desired with a minimumielectrostatic coupling and a large el'ectrom'ag netic coupling. -In'Fig. 8 show the aI'pplication of the present device-'intwo' difierent positions of an electron tube regenerative radio receiving circuit. The varioo'oupler 44 has its stator winding connected in -an' antenna ground system and its'roto r 8 con nectedto the input circuit of the 'electron tube regenerative receiver. The vario' coupler 45 has its stator 2 connected inthe grid circuit of the electron tube 46and its rotor connected in the plate circuit of the electron tube 46 whereby the desired feeding back of energy from the plate circuit to the grid circuit may be secured by adjustment of the relative'position of rotor 8 with respect to the stator 2, while selectivity in tuning may be secured by adjustment of the relative positions of the stator and rotor of the variocoupler 44 while response of the signal energy is secured in telephone receivers 47.

In Fig. 9 I show the application of the variocoupler to a radio frequency amplifier used at a radio receiver. The variocoupler 48 has its stator winding 2 connected in an antenna ground system and its rotorfi connected to the input circuit of electron tube 49 forming the first stage of the radio frequency amplifier. Electron tubes 50 and 51 are connected to form succeeding stages of radio frequency amplification while electron tube 52 is arranged as a rectifier and the energy amplified at audio frequency through the required number of stages represented diagrammatically by the single stage employing electron tube 54. The responsive de vice 55 is connected in the final stage of audio frequency amplification. As heretofore pointed out, the present form of variocoupler is particularly useful in radio frequency amplification by reducing to a negligible degree the passage of electrostatic energy from the antenna circuit to the input circuit of the radio frequency amplifier but providing a maximum electromagnetic coupling, obtaining thereby real tuning.

My arrangement provides means for introducing sufiicient electromagnetic coupling to neutralize the effects of capacity coupling by swinging the rotor to a position in which the electromagnetic coupling counteracts any remaining effects of electrostatic coupling, at which point zero magnetic coupling will be obtained. Further movement of the rotor in the proper direction gives magnetic coupling with great selectivity. enablin segregation of signals on slightly separated frequencies.

\Vhile I have described my invention in certain embodiments I intend no limitations other than are imposed by the scope of the appended claims.

What I claim is:

l. A variocoupler comprising a cylindrical support, a primary winding on said support, a flat spider web wound secondary mounted adjacent one end of said support, and means for rotating said spider web wound coil relatively to said primary coil.

2. A variocoupler comprising a cylindrical support, a winding carried by said support, a frame pivotally mounted within said support, a winding carried by said frame, the conductors of said winding being arranged at all times approximately in a plane passing through a diametrical line through said cylindrical support, and means for rotating said windings relative to each other.

3. A variocoupler comprising a tubular support, a winding carried by said support, a flat disk rotor comprising an insulated hub, arms radially positioned in said hub, a winding carried by said arms. and means for rotating said disk relative to said tubular support.

4. A variocoupler comprising a cylindrb cal member, a winding carried thereby, a fiat disk rotor comrising an insulated hub, an uneven numl er of arms radially positioned in said hub, a winding interwoven about said-arms, and means through one of said arms and attached to another two of said arms for pivotally mounting said disk relative to said cylindrical stator.

5. A variocoupler comprising a cylindrical member. a flat disk rotor comprising an insulated hub, arms radiating from said hub, a winding carried by said arms, means for pivotally mounting said disk within said cylindrical member comprising separate shafts, flange faces on said shafts, metallic fittings mounted on said cylindrical member, and resilient means between said fittings and said flange faces whereby said rotor may be adjusted in position relative to said cylindrical member.

6. A variocoupler comprising a cylindrical support, a inding carried by said support, a frame within said support, a pair of shafts for pivotally mounting said frame relative to said support, a winding carried by said frame, the ends of said winding be ing connected to said shafts, the conductors in said windings bein arranged at all times approximately in a plane passing through a diametrical line through said cylindrical support, and means for rotating said windings relative to each other.

A variocoupler comprising in combination a cylindrical member, a plurality of supporting faces separated by spaces over the area of the surface thereof, a stator winding carried by said cylindrical member, the turns of said winding contacting with said supporting faces and passing over said spaces, a fiat rotor pivotally mounted within said cylindrical member comprising a hub having arms radiating therefrom, a. rotor winding having its turns tangentially contacting with said arms wherebydielectric loss in said stator and rotor are minimized.

8. A variocoupler comprising a pair of windings. one of which is rotatable and the other stationary, the rotatable winding having extremely small electrical capacity with the stationary winding, and being movable into a plane approximately in the line of the axis of the stationary windings for introducing sufficient electromagnetic coupling to neutralize the effects of capacity coupling whereby said variocoupler obtains substantially zero electromagnetic coupling.

9. A variocoupler, comprising in combination ;1 cylindrical stator, e flat rotor pivotally mounted relative to said stator, a winding on said cylindrical stator, 21. sepa rate winding on said flat rotor, said last named Winding being arranged in such manner that only the width of a single turn lies directly adjacent said first named Winding.

10. A variocoupler comprising in combination a cylindrical stator, 21 flat rotor pivotally mounted relative to said stator, a winding on said cylindrical statora separate winding on said fiat rotor, said last named Winding comprising a conductor terminating adjacent the center of said rotor and being spirally Wound to an opposite terminal adjacent the periphery of said rotor, said winding being arranged in such manner that only the Width of one conductor lies directly adjacent said first named Winding whereby electrostatic transfer of energy between said windings is substantially nil.

ALFRED CROSSLEY. 

